Add str_ref_to_string fix

[Rustin170506]

close #11383
When type mismatch is &str -> String try to fix it.

[Rustin170506]

@Veykril
Could you please take a look? Thanks! 💚 💙 💜 💛 ❤️

[Veykril]

I'm a bit busy atm, will take a look when I find the time (unless someone beats me to it)

[Veykril]

We probably want this to be a bit more generally applicable if possible (and certainly not just text based by checking the types names) but in this instance this seems fine for now I think. We can figure out the better way afterwards since this is self-contained.

Thanks
@bors r+

[bors]

📌 Commit 638abba has been approved by Veykril

It is now in the queue for this repository.

[bors]

⌛ Testing commit 638abba with merge fc47ce5...

[bors]

☀️ Test successful - checks-actions
Approved by: Veykril
Pushing fc47ce5 to master...

[lnicola]

add-to-string.mp4

[rben01]

I feel like to_owned and into would be better options than to_string here. to_string means, essentially, "convert to the String that Display::fmt would give me". For &str, this happens to be the same as converting to an owned String, but that seems like a happy coincidence. to_owned and into are more explicit about the nature of the transformation taking place.